Characterizing and Fulfilling Traceability Needs in the PREDIQT Method for Model-based Prediction of System Quality

Our earlier research indicated the feasibility of the PREDIQT method for model-based prediction of impacts of architectural design changes, on the different quality characteristics of a system. The PREDIQT method develops and makes use of a multi-layer model structure, called prediction models. Usefulness of the prediction models requires a structured documentation of both the relations between the prediction models and the rationale and assumptions made during the model development. This structured documentation is what we refer to as trace-link information. In this paper, we first propose a traceability scheme for PREDIQT. The traceability scheme specifies the needs regarding the information that should be traced and the capabilities of the traceability approach. An example-driven solution that addresses the needs specified through the scheme is then presented. Moreover, we propose an implementation of the solution in the form of a prototype traceability tool, which can be used to define, document, search for and represent the trace-links needed. The toolsupported solution is applied on prediction models from an earlier PREDIQT-based analysis of a real-life system. Based on a set of success criteria, we argue that our traceability approach is useful and practically scalable in the PREDIQT context. Keywords-traceability; system quality prediction; modeling; architectural design; change impact analysis; simulation.